This Article, published in a symposium issue focusing on science and
expertise, traces the early reception of the modern expert witness. It
describes in some detail the widespread frustrations with expert
witnesses in court in the closing decades of the nineteenth century,
focusing in particular on the two most vociferous critiques: that
experts too often became partisans, mere mouthpieces for the party that
hired them; and that expert testimony was so frequently contradictory
that it confused and perplexed, rather than enlightened, the lay jurors
who heard it.

The
Article argues that these criticisms can only be properly understood by
recognizing two important aspects of how expert evidence was being
wielded and understood in this period. First, it is important to
recognize that even amidst the rampant complaints by the bench, bar,
and experts themselves, about the content and methods of expert
testimony, the actual use of expert evidence was simultaneously
increasing. Second, I argue that a key source of the dissatisfaction
with expert testimony was a disjunction between a set of idealized
expectations for scientific evidence and the practical realities of its
use in the courtroom. It was precisely because of what science was
thought to be able to offer to the process of legal decisionmaking,
that the spectacle of warring experts provoked such frustration and
anger. Science ought to have been able to offer proof more objective,
more certain, and more neutral than that of the lay eyewitness, or so
believed scientists and legal commentators alike. When it failed to do
so, this failure was frequently attributed to partisan excess or the
problems of adversarialism, rather than recognized as being, at least
in significant part, the result of unrealistic expectations for science
itself. In the conclusion, I suggest that this idealized conception of
science lingers with us today as well, and continues to influence how
we understand and critique expert evidence in court.